“I SUDDENLY BECAME LACTOSE INTOLERANT AFTER A BAD BOUT OF FOOD POISONING.”
A gastroenterologist explains why this can happen and what to do about it.
Sometime last August, I had a serious bout of food poisoning. My stomach has not been the same since. From just food poisoning, it turned into a long-drawn battle with an incredibly weakened digestive system and, surprisingly, a severe case of secondary lactose intolerance.
I’d never had a problem with dairy before this. I used to drink a cup of milk every other day and was a huge cheese eater. But since that August incident, I’ve come to accept that my stomach will churn and I’ll have the runs if I drink even the slightest hint of milk.
Initially, I thought it was because I was still recovering from food poisoning. But after seeing three doctors over the span of six months and tracking my diet, I realised that my biggest trigger for an upset stomach is dairy. The worst culprits so far are fresh milk, ice cream (the tragedy!) and yogurt.
I seriously never thought that this could happen to me – or anyone else for that matter. And I’d never heard of anyone developing lactose intolerance after food poisoning. So, just what happened to my gut health? I sussed out Dr Gwee Kok Ann, medical director and consultant gastroenterologist at Gleneagles Hospital, to find out more.
Is it possible to develop lactose intolerance after a bad bout of food poisoning?
DR GWEE Yes, it is possible. The enzyme responsible for digesting lactose, which is known as lactase, sits on the tips of villi, the finger-like projections on the internal intestinal lining. When there is an infection
involving the small intestine, the lactase is bound to be damaged, thus reducing one’s ability to digest and absorb lactose. Sometimes, after an episode of food poisoning, certain functions of the intestine may change. Intestinal movements may become faster and more sensitive to gas, and an imbalance of the naturally-occurring bacteria in the colon can also result in greater fermentation of lactose, which again leads to more gas. This damage to the intestinal lining may take up to two months to recover.
Is it possible to suddenly develop irritable bowel syndrome (IBS) after food poisoning?
DR GWEE An episode of severe food poisoning is a well-recognised cause of IBS. This is called post-infection IBS. Other common triggers of IBS include antibiotic treatment, majorly stressful life events and surgery to the gall bladder or pelvis.
Can someone who developed secondary lactose intolerance “train” their body to tolerate dairy again?
DR GWEE Most people with secondary lactose intolerance do not lose all their ability to tolerate lactose. There is usually some residual lactase enzyme on the intestinal lining that will allow for absorption of small quantities of lactose.
How well the intestine can handle the lactose load will also depend on the speed at which it moves through the intestine. The faster the intestinal movements, the worse the lactose intolerance will be. The trick is to avoid consuming dairy with substances that stimulate intestinal movements such as coffee, and to eat some food before consuming dairy.
Taking probiotics could also help to improve the balance of colonic bacteria in the gut, so that there is less gaseous fermentation of lactose, and reduce inflammation in the colon so that it is less sensitive to gas. It is also possible for probiotics to promote recovery of lactase enzymes and improve intestinal permeability.
Dr Gwee’s explanation sheds light on why I’m most intolerant to fresh milk, ice cream and yogurt since these are all non-solid items that pass through the intestinal tract very quickly. Currently, I’m slowly rebuilding my gut health by taking probiotic tablets daily. I’m also heeding the advice of Winnie Ong, fermentation expert and co-founder of local kombucha and kefir maker Craft & Culture, to order a mix of probiotic-rich foods like miso or kimchi whenever I eat out. This introduces different strains of good bacteria to my system to strengthen it.
Since I was officially diagnosed as being lactose intolerant earlier in January, I’ve also been consciously avoiding dairy. So far, my efforts seem to be paying off. From needing to clear my bowels five or six times a day, I now go just once in the mornings (my usual). My gut seems less reactive as well, but I still don’t know if I’ll one day be able to tolerate dairy again. The thought of never indulging in a scoop of creamy gelato definitely saddens me, but it’s a price I’m willing to pay if it means good gut health.
Sometimes, after an episode of food poisoning, certain functions of the intestine may also change. Intestinal movements may become faster and more sensitive to gas, and an imbalance of the naturally-occurring bacteria in the colon can also result in greater fermentation of lactose.